Temporary Installation in Firefox

This article describes how an add-on developer can temporarily install an add-on in Firefox for testing and debugging. The add-on will stay installed until you restart Firefox. You can use this method with any kind of restartless add-on, including bootstrapped extensions and Add-on SDK add-ons.

Note that this is not how end users should install add-ons in Firefox. End users will install add-ons by downloading and opening packaged add-ons that have been signed by Mozilla. To learn how a WebExtension developer can get such a packaged, signed add-on, see Publishing your WebExtension.

To install an add-on temporarily:

open Firefox

enter "about:debugging" in the URL bar

click "Load Temporary Add-on"

open the add-on's directory and select any file inside the add-on.

The add-on will be installed, and will stay installed until you restart Firefox.

Reloading a temporary add-on

Starting in Firefox 48, there's a new button labeled "Reload" next to the add-on's entry in about:debugging: